13745221 has 8 divisors (see below), whose sum is σ = 15733760. Its totient is φ = 11762928.

The previous prime is 13745213. The next prime is 13745233. The reversal of 13745221 is 12254731.

It is a happy number.

13745221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 13745221 - 2³ = 13745213 is a prime.

It is a super-2 number, since 2×13745221² = 377862200677682, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13745201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5020 + ... + 7258.

It is an arithmetic number, because the mean of its divisors is an integer number (1966720).

Almost surely, 2^13745221 is an apocalyptic number.

13745221 is the 2141-st hex number.

It is an amenable number.

13745221 is a deficient number, since it is larger than the sum of its proper divisors (1988539).

13745221 is an equidigital number, since it uses as much as digits as its factorization.

13745221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3123.

The product of its digits is 1680, while the sum is 25.

The square root of 13745221 is about 3707.4547873170. The cubic root of 13745221 is about 239.5432342484.

Adding to 13745221 its reverse (12254731), we get a palindrome (25999952).

The spelling of 13745221 in words is "thirteen million, seven hundred forty-five thousand, two hundred twenty-one".